If you have a decent amount of antimatter, a kilogram say, it doesn't matter (pun intended) whether it takes a millisecond or a minute for it all to be converted to energy.
A kg of energy is about that which is released by a 200 megaton bomb. Putting that much energy into a small volume is going to raise the temperature of the immediate surroundings quite substantially. I recommend wearing Ray-Bans and standing well back. A hundred km should be adequate.
First, the a^2+b^2=c^2 thing is for calculating with lengths, not velocities.
Secondly, you, (and the original poster), are using good old Euclidean geometry to calculate a "length". Your algebra is fine, it's just that space-time doesn't work the same way. The rule (for flat space-time) is that s^2 = x^2+y^2+z^2-t^2. Note the minus sign before the t. It's the presence of this minus sign that leads to many of the apparently counter-intuitive results of Special Relativity.
In General Relativity, not even the simple (+1 +1 +1 -1) metric works. The simple constants are, in general, replaced with functions involving the space-time co-ordinates. The effect is the same as curving the geometry; the curvature has an effect on test particles which is the same as the observed effects of gravity.
I realise that the above is over simplified and the purists are probably shuddering already, but to do the subject justice requires much more space and time than I have available right now.
At the simplest, this is just matter which is not glowing, which isn't all that exotic. Most of the matter you interact with in everyday life does not emit light
Not strictly true. On the assumption you are alive, you're at a temperature of 310K and are glowing very brightly in the infrared. A sufficiently large pile of material at 310K is very easily visible with an infrared telescope. Indeed, many of the cool clouds of dust and gas that have been discovered with IR telescopes are substantially cooler.
Paul
Re:get your terms correct
on
CPU Wars
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· Score: 1
Unlike Angstroms, which are just an abomination against nature (they should have just used nm or pm as appropriate).
Except when the Angstom unit was invented, all this micro, nano, pico stuff was still well in the future. The Angstrom unit is actually well designed: it's 1e-10 metres and it's about the size of an atom, which fits well with its original usage in atomic and molecular spectroscopy.
In history, during times when many men did not read, nothing much was written in the way of literature. This seems rather obvious to say it that way.
Yes and no. When literacy was rare, literature was also rare. However, great literature was written and even more great stories/poems/plays/... were passed down by oral tradition.
Some great literature has survived for over three thousand years, including the Epic of Gilgamesh and The Tale of the Eloquent Peasant to give but two examples from the Near East. There are many others from other cultures.
I've now read a whole bunch of comments saying that checksumming is useless because adding junk/serial numbers/whatnot will defeat the spam detectors. True, but irrelevant.
The intellectual property protection people have been thinking about this sort of problem for a long while now. Just as they want to be able to detect when something has been copied, the spam-haters want to detect when something is a copy. Both want to be successful in the presence of countermeasures. It's the same problem!
There's a vast amount of literature available out there. Any half-way decent search engine should throw up more than you can read in a reasonable time.
But there is no way for you to factor any of these numbers while you're still alive.
I don't intend dying that early - but who knows?
Some of us are already thinking about the 576-bit number with a $10k reward. It should be finished in less than a year. It's only ten times harder than the 512-bit number we completed two years ago. The 640-bit challenge is about ten times harder again, and so eminently reasonable in the near future.
The 2048-bit number is well beyond present capabilities.
Actually, we won't be sending out noise for that much longer. Digital radio/communication with encryption and compression should be completely entrpic (random). In other words, no distinct signal coming from us unless they know the DTV CoDec. And we're not even that noisy a radiation source.
Your first point illustrates nicely the difference between COMINT and ELINT. They don't have to be able to understand us to see that there is a message. If there is "noise" on a narrow waveband, it will be interesting in its own right. If there is noise on a whole group of narrow wavebands, that is very interesting.
Of greater concern is that all our comms will go over fibre and leave none to leak out into space.
Hmmn.... In _our_ (UK) recent census I could and did put Jedi simply because there was a specific exception for question ten from the legal requirements which apply to the other questions.
\begin{AOL}Me too! \end{AOL}
I also filled in the ethnic origin box as "Other: MONGREL".
In fact, in order to break RSA, you'd have to find a way to discover prime numbers without having to check them individually - that'd be quite an achievement and a mathematical triumph.
That's been known for a long, long time. We already know how to find prime factors faster than checking them individually. What's hard is finding them fast enough.
Others have pointed out the patronage issue.
It's also worth pointing out that, in 1560, if you wanted to hear a Mozart symphony, you pretty much had to go see Mozart.
It's also worth pointing out that, in 1560, if you wanted to hear a Mozart symphony, you pretty much had to have a time machine.
Once we can colonize (self sufficiently) beyond the solar system mankind will be able survive any one disaster.
If only it were so. A collision between two neutron stars anywhere within a few thousand light years will generate enough gamma rays to wipe out virtually all multi-cellular organisms.
Of course MS Research uses boxes running varieties of Unix as well as MS operating systems. Why on earth shouldn't they? They also use GNU Emacs under both Unix and Windows 2000. Again, why not?
If you want to see some more freely available source code targeted at a range of operating systems and written by the MSR Cambridge people, head over to the Glasgow Haskell Compiler page. While you are there, check out the Hall of Fame.
If you do a simple ideal gas calculation of the average velocity of an oxygen atom at 300K the velocity is much lower than the escape velocity of Mars (.7km/s compared to ~5km/s).
I know this isn't the best way to calculate this but its not a bad first approximation, so I was wondering what calculation you're using.
Indeed, this is not the best way to calculate this. There is a significant proportion of molecules which have much higher speeds than average. Check out some good books on classical thermodynamics.
In this age of billion dollar multi national corporations (which didn't exist when the constitution was drafted)...
Not quite true. Look up the history of the British East India Company, the Dutch East India Company, and the Hudson Bay Company some time, to give just three examples. Something over two centuries of inflation is enough to convert the resources they had available into gigabucks of today's money.
The British East India Company was founded in 1600, with a capital of 70,000 pounds - worth about $10M today. By the time the US constitution was being framed, they were running large chunks of the British Empire.
Slashdot Mirror
If you have a decent amount of antimatter, a kilogram say, it doesn't matter (pun intended) whether it takes a millisecond or a minute for it all to be converted to energy.
A kg of energy is about that which is released by a 200 megaton bomb. Putting that much energy into a small volume is going to raise the temperature of the immediate surroundings quite substantially. I recommend wearing Ray-Bans and standing well back. A hundred km should be adequate.
Paul
I'll try. There are two things wrong.
First, the a^2+b^2=c^2 thing is for calculating with lengths, not velocities.
Secondly, you, (and the original poster), are using good old Euclidean geometry to calculate a "length". Your algebra is fine, it's just that space-time doesn't work the same way. The rule (for flat space-time) is that s^2 = x^2+y^2+z^2-t^2. Note the minus sign before the t. It's the presence of this minus sign that leads to many of the apparently counter-intuitive results of Special Relativity.
In General Relativity, not even the simple (+1 +1 +1 -1) metric works. The simple constants are, in general, replaced with functions involving the space-time co-ordinates. The effect is the same as curving the geometry; the curvature has an effect on test particles which is the same as the observed effects of gravity.
I realise that the above is over simplified and the purists are probably shuddering already, but to do the subject justice requires much more space and time than I have available right now.
Paul
Paul
Paul
Then we'd all be smart-arses.
Paul
Not strictly true. On the assumption you are alive, you're at a temperature of 310K and are glowing very brightly in the infrared. A sufficiently large pile of material at 310K is very easily visible with an infrared telescope. Indeed, many of the cool clouds of dust and gas that have been discovered with IR telescopes are substantially cooler.
Paul
Except when the Angstom unit was invented, all this micro, nano, pico stuff was still well in the future. The Angstrom unit is actually well designed: it's 1e-10 metres and it's about the size of an atom, which fits well with its original usage in atomic and molecular spectroscopy.
Paul
Paul
I put down Jedi because I did care. I thought the question irrelevant and impertinent.
I very, very, nearly wrote in Frisbeetarian.
Paul
Yes and no. When literacy was rare, literature was also rare. However, great literature was written and even more great stories/poems/plays/... were passed down by oral tradition.
Some great literature has survived for over three thousand years, including the Epic of Gilgamesh and The Tale of the Eloquent Peasant to give but two examples from the Near East. There are many others from other cultures.
Paul
The intellectual property protection people have been thinking about this sort of problem for a long while now. Just as they want to be able to detect when something has been copied, the spam-haters want to detect when something is a copy. Both want to be successful in the presence of countermeasures. It's the same problem!
There's a vast amount of literature available out there. Any half-way decent search engine should throw up more than you can read in a reasonable time.
Paul
I don't intend dying that early - but who knows?
Some of us are already thinking about the 576-bit number with a $10k reward. It should be finished in less than a year. It's only ten times harder than the 512-bit number we completed two years ago. The 640-bit challenge is about ten times harder again, and so eminently reasonable in the near future.
The 2048-bit number is well beyond present capabilities.
Paul
Your first point illustrates nicely the difference between COMINT and ELINT. They don't have to be able to understand us to see that there is a message. If there is "noise" on a narrow waveband, it will be interesting in its own right. If there is noise on a whole group of narrow wavebands, that is very interesting.
Of greater concern is that all our comms will go over fibre and leave none to leak out into space.
Paul
Their offices were on Ursa Minor Beta.
Paul
\begin{AOL}Me too! \end{AOL}
I also filled in the ethnic origin box as "Other: MONGREL".
Paul
That's been known for a long, long time. We already know how to find prime factors faster than checking them individually. What's hard is finding them fast enough.
Paul
What billg meant to say was "... factor into prime numbers".
Paul
It's also worth pointing out that, in 1560, if you wanted to hear a Mozart symphony, you pretty much had to have a time machine.
Paul
I confided in Paul Leyland, an encryption expert working for Microsoft
Well *no wonder* it was cracked!
8-)
They actually did it the hard way. I spoke with Frederik to see how they cracked the code.
I'm impressed with their achievement.
Paul
Once we can colonize (self sufficiently) beyond the solar system mankind will be able survive any one disaster.
If only it were so. A collision between two neutron stars anywhere within a few thousand light years will generate enough gamma rays to wipe out virtually all multi-cellular organisms.
Paul
Of course MS Research uses boxes running varieties of Unix as well as MS operating systems. Why on earth shouldn't they? They also use GNU Emacs under both Unix and Windows 2000. Again, why not?
If you want to see some more freely available source code targeted at a range of operating systems and written by the MSR Cambridge people, head over to the Glasgow Haskell Compiler page. While you are there, check out the Hall of Fame.
Paul
I know this isn't the best way to calculate this but its not a bad first approximation, so I was wondering what calculation you're using.
Indeed, this is not the best way to calculate this. There is a significant proportion of molecules which have much higher speeds than average. Check out some good books on classical thermodynamics.
Paul
I wouldn't advise breathing a significant quantity of radon...
Paul
Not quite true. Look up the history of the British East India Company, the Dutch East India Company, and the Hudson Bay Company some time, to give just three examples. Something over two centuries of inflation is enough to convert the resources they had available into gigabucks of today's money.
The British East India Company was founded in 1600, with a capital of 70,000 pounds - worth about $10M today. By the time the US constitution was being framed, they were running large chunks of the British Empire.
Paul